Oracle ASM Filter Driver (Oracle ASMFD) maintains storage file path persistence and helps to protect files from accidental overwrites.

The following references introduce you to Oracle ASMFD:

• About Oracle ASM with Oracle ASM Filter Driver
  During Oracle Grid Infrastructure installation, you can choose to install and configure Oracle Automatic Storage Management Filter Driver (Oracle ASMFD). Oracle ASMFD helps prevent corruption in Oracle ASM disks and files within the disk group.